package lc

func climbStairs(n int) int {
	s := []int{1, 2}
	if n < 3 {
		return n
	} else {
		for i := 0; i < n-2; i++ {
			s = append(s, s[0]+s[1])
			s = s[1:]
		}
		return s[1]
	}

}
